foo.cc: In function ‘void Build(int, int, int)’:
foo.cc:90:18: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses]
   90 |         int mid=l+r>>1;
      |                 ~^~
foo.cc: In function ‘void Modify(int, int, int, int, int, int)’:
foo.cc:103:18: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses]
  103 |         int mid=l+r>>1;
      |                 ~^~
foo.cc: In function ‘ll Ask(int, int, int, int, int, int)’:
foo.cc:111:18: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses]
  111 |         int mid=l+r>>1;
      |                 ~^~